Leinster play Ulster at the Aviva Stadium tomorrow, while Munster made six changes to their side for Saturday's clash.
James Ryan will win his 100th cap for Leinster in their URC clash with Ulster at the Aviva Stadium tomorrow.
The second row is named alongside Brian Deeny, with Jack Conan captaining the side from number 8.
There's a new-look front row of Jack Boyle, Gus McCarthy and Rabah Slimani, while Suncroft's Sam Prendergast partners Luke McGrath at half-back.
Ulster have named their team with Wallabies prop Angus Bell set to make his first start for the province.
There's also a boost with Stuart McCloskey returning from injury at inside centre, while Ethan McIlroy is back in the match day squad for the first time since January.
Nick Timoney captains the side from openside flanker.
Munster have made six changes to their side for Saturday's clash away to the Ospreys.
Fineen Wycherley and Calvin Nash return from injury to start in the second-row and wing respectively.
Jack O'Donoghue will captain the side from blindside flanker, with Tadhg Beirne rested this week.
Craig Casey also drops out of the matchday 23, so there's a new half-back partnership of Paddy Patterson and Jack Crowley.

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